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Security and integrity

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Information modelling
& database systems

in this lecture we will consider briefly a range of issues concerning database applications
database security
aspects of security
access to databases
privileges and views
database integrity
view updating
integrity constraints

Database security
database security is about controlling access to information
some information should be available freely
other information should only be available to certain users
many different aspects of security:
legal issues
physical security
OS/network security
security policies and protocols
encryption and passwords
DBMS security

DBMS security support
DBMS can provide some security
each user has an account name and password
these are used to identify a user and control their access to information
DBMS verifies user’s password and checks their permissions whenever they try to
modify data
modify the database structure

Privileges

Privileges
SQL uses different privileges to control access to tables and other database objects
SELECT privilege
INSERT privilege
UPDATE privilege
DELETE privilege
the owner (creator) of a database has all privileges on all objects in the database and can grant privileges to other users
the owner (creator) of an object has all privileges on that object and can pass them on to others

Privileges in SQL
GRANT ON